At a recent Federation of Piling Specialists (FPS) Safety & Training meeting, the issue of Service Strikes was discussed or more specifically, the number of strikes the industry is seeing on an all too regular basis.
In fact, during the 12-month period to 30 September 2018, there were some 15 strikes spanning electricity, gas, water and other cables, with no statistically discernible spike or trough, just service strikes occurring on a regular basis. More noticeable, however, was that of these 15 incidents, 13 occurred with a ‘Permit to Work’ in place, so what’s going wrong?
Perhaps one clue could be elucidated from an incident reported by an FPS member company, in October 2018. In this instance, the site crew was instructed to replace a pile, but during the course of the installation power went out to the nearby business estate. The site crew immediately stopped works and the Electricity Provider was informed. Its initial report was that this was only a localised power cut and consequently, the site crew was instructed, by the Principal Contractor, to continue works. However, just five days later the site crew was informed that the replacement pile had damaged an 11KVa cable only 300mm below the piling mat.
Permits confirmed that a full site scan had been completed and that services were not marked as present. Worryingly, further utilities were subsequently discovered, and the Principal Contractor was left having to proof dig all the remaining pile positions.
This incident serves to highlight the importance of ensuring that a thorough investigation and scanning for buried services is completed by competent persons prior to breaking ground.
Another FPS Member has also very recently reported a cable strike and whilst the incident is still under investigation, it would appear that the cable struck was in this case known and had even been CAT scanned and a spray mark placed on site along with exclusion zone areas marked on the pile layout drawings. However, despite all this, the cable was not where it was indicated to be and was found outside of the exclusion zone.
As our data shows, and these two examples support, the majority of service strikes occur with a permit control system in place, yet these permits should signify that the Principal Contractor, as an integral part of their duties under CDM, has in fact carried out the requisite checks to ascertain the extent of, location of and making safe of all known services.
The FPS is therefore investigating to see how it can both influence and improve the Principal Contractor actions on their duty and not, tongue-in-cheek, leave it to the hit and miss approach of the piling contractor. After all, the piling contractor is contracted to install foundations and deploy geotechnical solutions etc., not as a specialist service location contractor.
Information and advice is available; HSG 47 Avoiding danger from underground services for example, provides guidance aimed at all those involved in commissioning, planning, managing and carrying out work on or near underground services. As well as useful to the owners and operators of such services, it outlines the potential dangers of working near underground services and gives advice on how to reduce any direct risks to people’s health and safety, as well as the indirect risks arising through damage to services. A key component of the document covers both the planning of work and the locating and identifying buried services.
British Standards Institution too, with its PAS 128 Specification for underground utility detection verification and location, is another excellent document which specifies requirements for the detection, verification and location of existing and new underground utilities. Worth noting, it sets out the accuracy to which the data is captured, the quality expected of this data and a means by which to assess and indicate the confidence that can be placed in the data. With the availability of excellent guidance and specifications for locating underground cables and utility networks it is clear something is going wrong somewhere.
Over the coming months the FPS’s Safety & Training Committee will be looking at ways of tackling this issue as well as continuing to highlight the problem and the duties Principal Contractors have of ensuring thorough investigative service location work is carried out prior to the commencement of any works which involve breaking ground.
If you would like to contribute to the work, please get in touch via email – fps@fps.org.uk